yaso

I hope you bare with me here, I'm a brand new newbie in Forge. I want to achieve the ability to monitor living entities. i.e. on spawn I would be able in each time interval to get each of the creatures position and for starters write to log. I couldn't find any tutorial that would bring me to a step on the right direction. Is it possible to get entity positions? Could you please share some links to documentation if some exists? Many thanks